Since macular degeneration has become the leading cause of the loss of useful vision in industrialized countries, any applicable experimental model would seem to be most desirable. Subretinal neovascularization in the macular region has been produced in stumptail monkeys. Similar techniques of injection from either the scleral or the vitreal side will produce neovascularization in the macula but not in the retinal periphery. One of the most important aspects of this study has been to demonstrate the necessity of chronic and long term follow-up of the monkeys. Frank neovascularization has been observed to wall itself off and seal and no longer progress after a year of progressive expansion of the neovascularization. Thus, the natural history of this experimental model must be thorougghly investigated before the therapeutic modalities such as argon laser, etc. are investigated. Cystoid maculopathy has been investigated in our other monkeys. By performing intracapsular cataract extraction with purposeful loss of vitreous and incarceration in the wound, this was not produced. However, by increasing the anterior chamber inflammatory reaction with immunologic means of stimulating an implanted lymph node or endotoxin injection in a sensitized animal, this could be produced. This was most difficult and not as reproducible as one would like.